A Case of Paraneoplastic Bullous Pemphigoid in Association with Squamous Cell Carcinoma of Lung

Bullous pemphigoid is a chronic, autoimmune, acquired subepidermal blistering disorder. It is idiopathic in origin, and mainly seen in elderly individuals. Association between bullous pemphigoid and internal malignancies is reported in the literature, but the exact causal relation is not established. Paraneoplastic bullous pemphigoid is rarely reported in lung cancers, especially in squamous cell variety. So their presence should raise the suspicion of various internal malignancies including lung cancer. It is presented mainly with tense, large blisters over the erythematous base or over normal skin. Subepidermal blisters with tissue eosinophilia are characteristic histopathological features of bullous pemphigoid. Direct immunofluorescence shows linear deposits of IgG - complement complex along the dermoepidermal junction. Conventional treatment of bullous pemphigoid along with treatment of lung cancer (surgery, chemotherapy, radiotherapy) may result in successful resolution of skin lesions. Here, we report a rare association of paraneoplastic bullous phemphigoid and squamous cell carcinoma of lung in a 76-year-old male to increase the awareness among the clinicians regarding this variety of cutaneous paraneoplastic manifestation of lung cancer.